Thinking of buying this car, has a power issue...

I may buy this 1991 Integra LS. It's in good shape and great price, but it has one issue. The car won't start. He says when he turns the key the dash lights come on, but radio won't power, AC won't power etc. I don't think the motor cranks either. He said it's like the car isn't getting power.

Any ideas what this could be? I'm gonna go take a look at the car tomorrow or wed. and try to figure it out. Burnt fuses, relays or bad ignition switch/harness maybe? I'm kinda stumped.

EDIT: Guy just sent me this for what it's worth:

"dash lites up ? NO headlights , no radio , no other electric part . Doesnt not crank i havent tried push starting yet."